Fluid pressure diaphragm



Nov. 9, 1943.

D. E. MULHOLLAN FLUID PRESSURE DIAPHRAGM Filed Feb. 3, 1941 3 Sheets-Sheet 5 .279500 I: Me/L/ oLLflN Patented Nov. 9, 1943 Eum) PRESSURE DIAPHaAGr/r David E. Mulholand, Reading, Pa. l A n tioartrumy 1941,'SriaNo. 371273 v Y 'phragms and more particularly to fluid pressure diaphragms arranged to operate sequentially and in op'p'osite directions for controlling the move- 'inent of a` member interposed between and` operatively associated with the said diaphragms.

The principai object of the invention, generany considered, isto provide a fluid pressure diaphragm having a fiexible diaphragm member operating`- between fixed and movable plates.

Stihanother object of the invention is to'proi vide a diaphragm member operating within a housing, the walls of said housing being-adapted to engage and guide the side portios of meda phragm and to provide aplate member overlving t the said diaphragm and formn'g a rigid'platform movable with the same and in turn guided by the .sidewalis ofthe said diaphrag'm chamber.

' Still another object of the "invention to provide a pair of oppositely facing'diaphragm chambers and to position 'in each an oppositely acting diaphragn and to. provide the tw`o diaphragms i with fluid pressure connections so that the same may operate in sequence. e Still another object of theinvention is to pro- Vide means whereby the Operating face of the diaphragm is uniform as to area throughout its stroke at all pressur'eswhichwill operate it. i

Other objects of the invention and the mechai nism by whichithe same are accomplished 'will be pointed out in the specificatiom the novel features .thereof being 'set forth in the appended claims. r e i For convenience I have illustratd my invention in connection with the mechanism disolosed p in my prior Patent No. '2,181463. dated January 16, 1940, and while the present invention 'may he advantageously employed with the Construction illustrated in the accompanying drawingjs, -it is to be understood *that the invention isnot limited to such application *but-may be advaninvention reiates to fiuid pressu re diau 'through the associated diaphragm and their 'Operating parte. 7 i i Figure 3 is a View on a large scaie of a single v diaphraigm illustrated in Figure 2.

Figure 4 is a diagrammatic View of the piping 'connection 'employed with the specific diaphragm Construction' illustrated' in Figures 1 and 2.

The grinding machine as illustrated is provided with a` grinding roll "i, a work supporting roll 2 and a back-up roll 3, the grinding roll having "an abrasive surface`4 and the work supporting roll having a yielding` surface 5 to form a friction gripping engagement between the back-up roll and the work supporting roll. The back-up roll,

f the work supporting roll, and the adjusting'wo'rk supporting guides or skid tahles E are all carrid bv apvoted beam 'Lonly a fragmentary portion The work guide members or skid'tables E are porting ro11-2 by means of the rotating shafts 8,

i above, the pivoted carriage 1 is counter-bal- 'anced and operates between iimit'stops, the lower tageously utilized in a number ofplaces where precision of movement and control of such movement through a limited range is desired.-*

Throughout the specification and drawings 'like parts are designated by likereference characters.

In the drawings: i i Figure 1 is a vertical'longitudina'l cross-sectional View of a fragmentary portion of a grinding i machine, illustrating .in 'full lines the position of one pair of diaphragms.

Figure 2 is a cross-sectionai View showing the i n back-up roll, the work supporting roll and associat`ed parte in fulliines and across-sectional View the threaded portions &of which engage in corre- -spondingly threaded portions !D of blocks ll which ai'e rigidly connected to'the skid tables or guides'. Positioned above the work supporting 'guides` are the chambered members !2 through which, 'in 'the operation of the machine, the coolant fluid passes; V i

As fullv disclosed ;in my `prior patent' noted limit stop being shown in Figure 1 and comprising a housing member !3 in which is slidably received a block M which is suitably` recessed -ai`d-threaded `so`as to engage within the recess !5 the thre'aded portion IG- of the screw I'L the latter being operated by intermeshing hevel pinions !8 in order that theabutment block |9 carried tytloej sliding block M may be raised or lowered' as desired, the upper face of the abutment 19 being adapted to be contacted by the` stop member 7.10 carried by the p'voted carriage 'L` ;In Figure 2 I have=` i11ustrated in full lines the back-up roll 3 and the work supporting roll ;2 and the bearing menbersfor these rolls are indicated, respectively, by the reference characters Zi and 22. Housed withinthe' hearing 22 is athedrivng mechani'sm which operatest drive the hack-up roller and through the latter the `work supporting roller 2; i

The reference numera1s`23 indicate the support for theskid or guide tables'L It will be noted j that'thebearihgmembers 2 l and 22 are supported on'. the carriage 'I and hence both rollers 2 and 3 are carried by and movable with the member 1. The numeral 24 designates the base or fo'undation upon which the diaphragms to be described are rigidly mounted.

As indicated above, the diaphragms 25 are arranged in oppositely directed pairs and since each diaphragm is identical the description of one will sufice for the description of the entire assembly. There is provided a baseplate 26 which is secured to a foundation member 21 which may be either the base of the machine 24 or the base plate of a U-shaped member 23. The plate 26 is provided, with a plurality of counter-sunk openings 29 leading from the inner' face into which extend bolts or screw 36 by which the plate 26 is secured to the foundation member 21. On the opposite face of the plate 26 is also provided a plurality of counter-sunk openings 3| through which extend the screws or bolts 32 by means of which the' c'ylindrical collar 33 and the projectirg' portion34 'of the fiexible member 35 of the diaphragm are rigidly secured and by means of which a fluid tight connection is made between the base plate 26 and the flexible portion 35 of the diaphragm. i

The inner cylindrical wall 36of the collar 33 is polished so as to permit the free movement within the same ;of a cap member or plate 31, the

' lower face of which Contacts the upper face of the fiexible diaphragm 35. The plate 31 is preferably provided with a boss 38, the purpose and object of which will be hereinafter described.

The diaphragm is provided with one or more folds 39 in orderythat; upon the admission of fluid pressure through the port 40 in the base plate 26, the diaphragm may expand, without loss of area of the portion that Contacts the plate 31, forcing the plate 31 upwardly and the upward limit of movement is, of course, measured by the length .of the flexible portion of the diaphragm between the edge of the horizontal portion en- 'gaging the plate 31 and the edge formed by the inner surface 36 of the collar33. A plurality of holes 36a are provided in the cylindrical wall of-the collar 33, preferably spaced around the periphery and located so as to be covered by the flexible member of the diaphragm. These holes leading through thewall permit any air trapped in the folds 33 ot the diaphragm member 35 to be expelled as pressure is applied to the dia-cz' phragm and also provide for the admission of, air.

so as to break the sea between the diaphragm `member and the wall 36 When the internal 'pressure on the diaphragm is released.

The portion of the diaphragm member 35;` which Contacts the plate 31 is of greater thickness and rigidity than that portion of the diaphragm which constitutes the folds. This additional thickness serves to limit the stretching under pressure of the folds orming the side walls-- of the diaphragm and in connection with the 'plate 31 acts to apply the selective fluid pressure per square inch to a constant number of square inches of the plate 31 throughout the or movement of the diaphragm'. V

The upper diaphragm is made exactly as de-` scribed and interposed between the boss 138` of each of the plates `31 'andcarried by a yoke mementire stroke.

gages a similarly formed collar 52 on the oppo-` site face of the yoke member 4| so that when the v parts are assembled, as shown, in Figure 3, the plunger member 42 is rigidly united with the' yoke 4| so that any movement of theplunger 42 will impart to the yoke ll a corresponding movement. The arms 53 of the' yoke ?41 are rigidly secured to the correspondingly formed portions .54 carried by the member 1. I have, for convenience, illustrated these parts 53 and 54 as being connected by bolts and nuts 55. I It will be apparent from the foregoing description that when the valve mechansm hereinafter described is operated so as to admit fluid pres' sure within the upper diaphragm' opening 56 the fiexible diaphragm 35 will be expanded, as illusv trated-in F'gure 3, forcing the boss 38 of the plate into contact with the curved head of the plunger member andforcing, the yoke member 4 and the pivoted carriage 1 to move downwardly so as to cause the stop 20 of the latter to engage the be aring block IQ. In this position, ow-

.ing to' the fact that by the weight of the plate 3? the lower fiexible diaphragm 35 has been forced into contracted position, the curved head 51` of the member 41 is spaced from the boss 38 of the plate 31. When it'is desired to reverse the movement, the fluid' ,pressure in the dia,- phragm opening 56is released and fluid'pressure admitted through the pipe 40 to the chamber beneath the lower flexible diaphragm, causing the same `to move upwardly until the boss 38 of this diaphragm member engages the head 51 and by this means causing the yoke.4l on the ,car-s riage 1 to move upwardly, 40.

otal axis of the carriage 1.

By providing the curved head 45. and 41, the 'I v rocking movement imparted to the plunger member 42 will not aect, the, distribution of pressure 'from the bosses 38 nor will the movement of the yoke tend to cant or otherwise change the position of the plates 31. By providing the plates 31 with raised bosses 38 connected at spaced points to the side wallsgthereof by ribs 58 I provide an exceedingly rigid plate and thus prevent any distortion of the upper surface of the diaphragm and hence also cause the plates 31 to move as a unit within the confining wal1 -36 of the collar 33.

ber 4| is a two-part plunger member generally "illustrated in 'Figure 2.

nates a fluid pressure tank fed by means of a pipes In Figure 4 I have illustrated means for operg pairs of diaphragms atin in sequence the two I The numeral 59 desigwhich leads'to a fluid shown.

pressure pump, not

lead respectively to pipes leading to the openings 4| formed in' the members'. I

It will be ob-vious from the disclosure and this description that when the four-way valve is inlthe.

position illustrated in Figure 4- pressure is admitted tothe two lower diaphragm base plates and fluid pressure is exhausted from the two up- .per diaphragm chambers through the'pipe 63 and the outlet pipe 66 from the four-way valve and 'consequently upon a movement of the four-way valve the pipe 54 is connected to the exhaust and the pipe .63leading.to 'the upper`dia`- y pipe formed on the yoke member g 4l. Likewise the end 51 of the member 41 enrotating about the piv- Leading from the tank 59 is a pipe 6|fi 'which connects to a four-way valve 62 from which two pipes 63 'and 64 the upper. and lower diaphragm chambers. These pipes are branched, as shown at 65, the branch' u sible, knowing the area of the diaphragm chambers 56 and the amount of fluid pressure, to closely and accurate regulat the pressure imposed upon the yoke 41 and through the latter upon the pivo-ted carriage 'I so that the degree of pressure'of the work supporting roller against the work can be regulated with great nicety.

As an example of theresults which have been` obtained with this system of pressure control, which entirely eliminates the friction of moving parts, when applied to a grinding or polishing set up such as is illustrated in Figur 2, I have found it possible to surface a sheet of Celloph'ane whose thickness is approximately cne-half of one-thousandth of an inch; This surfacing of the Cellophane sheet is sufiicient to remove the shine on the surface but represented such a small fraction of an inch in the reduction of the thickness of the Cellophane sheet asto be incap'able of measurement by ordinary methods. I have also found 'it possible to grind the surface of the Cellophane sheet so as to materialiy reduce the thickness of the sheet without the destruction of the continuity of the sheet.

While I have described my diaphragm Construction as pointed out above, it will be obvious to those skilled in the art, that the diaphragms are capable of being utilized in a large number of other devices and may be advantageously employed to regulate pressures upon movable objects in connection with any type of mechanism.

Having thus described my invention what I claim and desire to secure by Letters Patent is:

1. A device of the character described comprising a base plate, an open ended collar connected thereto, a* flexibie and expansible `diaphragm member having a ring-shaped portion interlockingly interposed between said plate and one end of said collar, a second plate slidably engaging the interior wall of said collar, said second plate being movable with the said diaphra'gm, said diaphragm when expanded being supportingly engaged by the inner wall of said collar, and a plunger having a spherical end extending within said collar and spaced therefrom, said spherical end being adapted to rockably engage the opposite face of said plate'` from that engaged by the diaphragm. I I

2. A device of the character described comprising a solid base plate having a centrally disposed opening therein and leading to one face thereof, an open` ended metal collar mounted on said base plate and having a cylindrical inner surface, a fiexible and expansible diaphragm member within said 'c0llar, said diaphragm having a ring portion interpc-sed between said base plate and collar and forming with the latter a fluid-tight joint,

` the wall of said diaphragm when expanded being and movable therewith within said collar, and a `mounted within said respective collar, and a supportingly engaged by the cylindrical inner surface of said collar, a c'ylindrical follower plate slidably engaging the interior wall of said collar and engaging the upper surface oi' said diaphragm plunger member engaging the face of said follower opposite to said diaphragm, said plunger having rocking engagement With said follower.

3. A device of the character described comprising a pair of oppositely disposed base plates each of which is provided with an opening leading to the face adjacent th other base plate, fiexible 'and expansible diaphragm members each having extending from one edge a ring-shaped portion, a pair of metallic collars each of which is adapted to engage the ring-shaped portion of one diaphragm, means for `connecting each collar 'and diaphragm to the adjacent base plate, the inner wall of each collar-supportingly engaging the side wall of the respective diaphragm on the expansion thereof, and plunger means interposed between the said diaphragms and extending within the said collars, said means being actuated by the movement of either diaphragm from normal position. i

4. A device of the character described comprising a pair of oppositely disposed base plates each of which is provided withvan, opening leading to i the face adjacent the other base piate, fiexible 'and expansible diaphragm members each having extending from one edge arrng--shaped portion, a-pair of metallic collars each of which is adapted to engage the ring-shaped portion of one daphragm, means for connecting each collar and diaphragm to the adjacent base plate, the inner wall of `each collar supportingly engaging the side wall of the respective diaphragm on the ex-' v pansion thereof, a follower member engaging the outer surface of each diaphragm and slidably plunger member interposed between said followers and normally engaging one of said followers upon the movement of the associated diaphragm from closed position.

, DAVID E. MULI-IOLLAND. 

